Preheat oven to 400F. Line a baking sheet with baking parchment and fit a pastry bag with a pastry bag with a plain 1/2-inch round tube.Combine water,salt,sugar, and butter in a heavy saucepan. Bring to a boil and add flour all at once. Stir vigorously for 2 minutes over medium heat until well amalgamated and mixture pulls away form side of pan. Transfer to bowl of electric mixer and beat for 3 to 4 minutes at low-speed to cool mixture. Add eggs one at a time, making sure each in incorporated before adding the next one. Beat at medium-high speed until mixture is smooth and shiny. Transfer to pastry bag and pipe into desired shapes (see next page). Bake for 20 minutes or until well puffed and golden.